In one of my favorite movies, Training Day (2001), street-smart detective Alonzo is about to hit the gas on his tricked-out, black 1979 Chevrolet Monte Carlo to shake down a small-time Los Angeles drug dealer, when the rookie Jake picks up the radio to call it in.

"Stay off of the Rover," Alonzo threateningly tells him.

Of course, Alonzo could have meant that he was about to cross the line and didn't want anyone to know about it. Or perhaps someone might see Jake talking on the radio and know that they were cops. Or Alonzo could have meant that Jake needed to get his head out of headquarters and into the moment.

In any case, Alonzo makes two great points. First, you don't have to share everything all the time. And secondly, what matters most is what's happening right in front of you.

Geek Culture Equals Digital Distractions

Alonzo's warnings are true for all of us -- that is, we're having a crisis of digital distraction courtesy of the geek culture. It's not just in fictional movies, either. Smartphone theft and muggings in the San Francisco Bay Area have been booming, made possible because people are staring into screens rather than paying attention to thieves getting ready to rob them of their gadgets.

The theft has become so common that it now has its own name, "Apple Picking," because most of the stolen phones are iPhones. I once witnessed such a theft on a BART train heading into the city a couple of years ago. I, too, was deep into my iPhone listening to music and surfing over Safari when a couple of kids swiped a woman's phone and took off. It was perfectly timed as the train doors opened.

Two weeks ago, San Franciscans were seized with shock and disbelief over an apparently random killing. Nikhom Thephakaysone allegedly shot and killed Justin Valdez for no reason. Police believe Thephakaysone was hunting for a stranger to kill.

This sad event might have been prevented had people been paying more attention. Moments before Thephakaysone fired a shot in the back of Valdez, Thephakaysone was caught on a public camera on a crowded train. The camera shows him whipping out a .45-caliber pistol several times, yet none of the dozen people around him noticed because their noses were buried in their devices.

"These weren't concealed movements -- the gun is very clear," says District Attorney George GascÃ'Â³n. "These people are in very close proximity with him, and nobody sees this. They're just so engrossed, texting and reading and whatnot. They're completely oblivious of their surroundings."

Stop Texting and Look Around

Jack Nasar, an Ohio State University professor in city and regional planning and specializing in environmental psychology, studied the dangers of cell phone distractions in 2008 and found upsetting results, according to an SFGate story. His research team planted fake vomit on sidewalks and hung posters reading "unsafe," yet people on cell phones often missed the signs.

In other words, they acted much like distracted drivers who text on their phones, which brings up another maddening episode in our emerging digitally distracted world.

Texting drivers have swerved into other lanes, run through stop signs and lights, and caused countless crashes, which prompted California to ban texting and driving. Simply put, texting drivers are a menace. But that hasn't stopped people from texting and driving.

In fact, texting driver sightings are a regular occurrence. Chances are you'll see one the next time you get in your car. Whenever I see drivers looking down on their cell phones, I think of Alonzo.